Stars above tombs of ancient Persian kings in Persepolis in Iran
This hour-long exposure shows the circular trails stars make as a result of the Earth's rotation. In the foreground, 2,500-year-old tombs of ancient Persian kings tower high above a site near Persepolis in southern Iran.
Iranian photographer Babak Tafreshi has won the 2009 Lennart Nilsson scientific photography prize. According to the award panel, his images "reclaim a night sky that most modern people have lost" – see some of them here.